How much physical diversity can a species support?

by Roger Bourke White Jr., copyright January 2019

Lesson being learned

One of the inadvertent lessons that the dog's symbiotic relation with humans is teaching us is how much physical diversity a species genome can support. The members of most species look pretty much the same. This is because they are constantly being pushed by their living circumstances to be a high performance adaptation to the ecological niche they are living in. They look the same because they function the same.

The niche dogs are living in is different. They thrive when they please their humans, and it turns out humans enjoy diversity in their pet dogs. The result: dogs come in enormous variety. Instead of pressing the limits on performance in their niche they are pressing limits on how diverse they can become and still be part of the species, as in, they can still mate with each other.